Genus: Amblotherium OWEN, 1871
Etymology: Greek, ambloo, “abort” and Greek, therion, “beast, mammal”: Aborted mammal.
= Achyrodon OWEN, 1871
Etymology: Greek, akhyros, “needle-point” and Greek, odon, “tooth”: Needle-pointed tooth.
= Laodon MARSH, 1887
Etymology: Greek, laos, “stone” and Greek, odon, “tooth”: Stone tooth.
= Odontostylus TROUESSART, 1898 non GRAY, 1840 (Odontostylus, Mollusca)
Etymology: Greek, odon, “tooth" and Greek, stylos, “pillar."
= Stylacodon MARSH, 1879
Etymology: Greek, stylos, “pillar”, Greek, ake, “point”, Greek, odon, “tooth”: Pillar point tooth.
= Stylodon OWEN, 1866 non BECK, 1837 (Stylodon, Mollusca, Acavidae)
Etymology: Greek, stylos, “pillar” and Greek, odon, “tooth”: Pillar tooth.
= Trouessarti COSSMAN 1899 non CANESTRINI & KRAMER, 1899 (Trouessarti, Arachnida, Trouessartiidae)
Etymology: In honor of Edouard Louis Trouessart (1842-1927), German zoologist.
= Trouessartiella COSSMAN, in TROUESSART's Cat. Mamm. 1899
Etymology: To replace Trouessartia.

Species: pusillum (OWEN, 1866) OWEN, 1871
Etymology:
= Stylodon pusillus OWEN, 1866
= Achyrodon pusillus OWEN, 1871

Holotype: BMNH M5632

Locality: Durdlestone Bay, Swanage, Dorset County, England, Southern United Kingdom.

Horizon: Purbeckian.

Biostratigraphy:

Age: Tithonian Stage, Upper Malm Epoch, Late Jurassic.

Material: Fragment of left ramus, outer aspect, with LP4 and LM1-7.

Referred material:

BMNH 47756: Right lower jaw with 5 molars, associated left lower jaw with fragments of premolars and molars and associated right upper jaw with 4 molars.

BMNH 47757: Left mandibular ramus with LI1-2, LC, LP3-4, and LM1-7.

BMNH 47759: Left ramus, external aspect, with LM6-7 and roots of bases of P4 and LM1-5.

BMNH 47761: Left ramus, external aspect, LP4 and LM1-6.

BMNH 47783: Part of left maxilla with 2 premolars and fragments of 3 molars.

BMNH 47802: Part of right maxilla with a premolar and 3 broken molars.

BMNH M10927: Part of left ramus with LC and LM1-7, internal aspect.

BMNH 47743: Part of left ramus, external aspect, with LI2-4, LC, LP1, LP3 and LM1-2.

 


= Amblotherium soricinum OWEN, 1871
Etymology:

Holotype: BMNH 47752

Locality: Durdlestone Bay, Swanage, Dorset County, England, Southern United Kingdom.

Horizon: Purbeckian.

Biostratigraphy:

Age: Tithonian Stage, Upper Malm Epoch, Late Jurassic.

Material: Right ramus, internal aspect, nearly complete, with LI1-4, LC, LP1-4, LM1-6.

 

= Stylodon robustus OWEN, 1871
Etymology:

Holotype: BMNH 47762

Locality: Durdlestone Bay, Swanage, Dorset County, England, Southern United Kingdom.

Horizon: Purbeckian.

Biostratigraphy:

Age: Tithonian Stage, Upper Malm Epoch, Late Jurassic.

Material: Left ramus, external aspect, LP4, LM1 and LM3-8.

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Species: nanum (OWEN, 1871)
Etymology:
= Achyrodon nanus OWEN, 1871

Holotype: BMNH 47745

Locality: Durdlestone Bay, Swanage, Dorset County, England, Southern United Kingdom.

Horizon: Purbeckian.

Biostratigraphy:

Age: Tithonian Stage, Upper Malm Epoch, Late Jurassic.

Material: Right ramus, internal aspect, with LP3-4 and LM1-8.

Referred material:

BMNH 47785: Left ramus, internal aspect, with LM2-5 and LM8.

BMNH 47786: Fragment of right ramus, internal aspect, with 2 broken molars, a right maxilla with the last 2 premolars and all seven of the molars.

BMNH 48403: Right maxilla with LM1-6.

BMNH 47783: Left ramus, internal aspect, with 4 molars.


= Stylodon pusillus OWEN 1871
Etymology:

Locality: Durdlestone Bay, Swanage, Dorset County, England, Southern United Kingdom.

Horizon: Purbeckian.

Biostratigraphy:

Age: Tithonian Stage, Upper Malm Epoch, Late Jurassic.

Material:

BMNH 47758: Right and left mandibular rami, both internal aspect, with most of the teeth present, although somewhat broken, and fragmentary skull, a number of vertebrae and ribs.

BMNH 47760: Left ramus, external aspect, with LP4 and LM1-7.

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Species: validus (MARSH, 1880)
Etymology: Latin, validum, “strong.”
= Stylacodon validus MASRH, 1880

Holotype: USNM 2722

Locality: Reeds YPM Quarry 9, (Mammal Quarry), T22N, R77W, Sec. 12, Como Bluff, Albany County, Wyoming.

Horizon: Brushy Basin Member, Morrison Formation.

Biostratigraphy: Zone 3.

Age: Upper Part, Comobluffian age, Kimmeridgian Stage, uppermost Malm Epoch, Late Jurassic.

Material: Lower jaw and teeth.
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Species: gracilis (MARSH, 1879) SIMPSON, 1927
Etymology: Latin, gracilis, "slender."
= Stylacodon gracilis MARSH, 1879

Holotype: YPM 11883

Locality: Reeds YPM Quarry 9, (Mammal Quarry), T22N, R77W, Sec. 12, Como Bluff, Albany County, Wyoming.

Horizon: Brushy Basin Member, Morrison Formation.

Biostratigraphy: Zone 3.

Age: Upper Part, Comobluffian age, Kimmeridgian Stage, uppermost Malm Epoch, Late Jurassic.

Material: Left lower jaw in matrix, anterior fragment, toothless, inner aspect. Middle portion, matrix impression only, posterior portion, outer aspect with p4, m1-4, p3 preserved separately.

Referred material:

AMNH 101134: Left ramal fragment with one molar and three alveoli anterior to it.

YPM 13732: Right lower jaw with m5-7.

YPM 13731:

YPM 13733:

USNM 2142:

 

Note: According to MERRILL, 1907

MARSH, 1879

Holotype: USNM 2693

Locality: Como Bluff, Wyoming.

Horizon: Member? Morrison Formation.

Biostratigraphy: Zone?

Age: Age?, Stage?, Malm Epoch, Late Jurassic.

Material: Left ramus containing nearly all the teeth.

 

ENGELMANN & CALLISON, 1998

Locality: Quarry face as exposed inside the Dinosaur National Monument Visitor Center, Carnegie Quarry, Vernal, Uintah County, Utah.

Horizon: Brushy Basin Member, Morrison Formation.

Biostratigraphy: Zone 3.

Age: Upper Part, Comobluffian age, Kimmeridgian Stage, uppermost Malm Epoch, Late Jurassic.

Material:

DINO 10719, 10721, 10722, 10727, 12783, 12786, 12788, 12791, 12792: Teeth.

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Species: venustus (MARSH, 1887)
Etymology:
= Laodon venustus MARSH, 1887

Holotype: USNM 2142

Locality: Reeds YPM Quarry 9, (Mammal Quarry), T22N, R77W, Sec. 12, Como Bluff, Albany County, Wyoming.

Horizon: Brushy Basin Member, Morrison Formation.

Biostratigraphy: Zone 3.

Age: Upper Part, Comobluffian age, Kimmeridgian Stage, uppermost Malm Epoch, Late Jurassic.

Material: Left lower jaw in matrix inner aspect, with p4 and m1-7.
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Species: debilis SIMPSON, 1927
Etymology:
= Dryolestes gracilis MARSH, 1881

Holotype: YPM 11821

Locality: Reeds YPM Quarry 9, (Mammal Quarry), T22N, R77W, Sec. 12, Como Bluff, Albany County, Wyoming.

Horizon: Brushy Basin Member, Morrison Formation.

Biostratigraphy: Zone 3.

Age: Upper Part, Comobluffian age, Kimmeridgian Stage, uppermost Malm Epoch, Late Jurassic.

Material: Left lower jaw with m1-6 and roots or alveoli of other teeth.

Referred material:

AMNH 101133: Two right ramal fragments, one segment has 3 molars, the other segment consists of LM6, alveoli for LM7-8, and the rear portion of the jaw.

YPM 13728: Right lower jaw in matrix, outer aspect, with m1-6

YPM 13730: Posterior part of lower jaw, in matrix, inner aspect, with m5-7, the outer aspect of m6-7.

YPM 13734:

USNM 2726:

 


ENGELMANN & CALLISON, 1998

Locality: Quarry face as exposed inside the Dinosaur National Monument Visitor Center, Carnegie Quarry, Vernal, Uintah County, Utah.

Horizon: Brushy Basin Member, Morrison Formation.

Biostratigraphy: Zone 3.

Age: Upper Part, Comobluffian age, Kimmeridgian Stage, uppermost Malm Epoch, Late Jurassic.

Material:

DINO 10718, 10723, 10724, 12860: Teeth.

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Species: megistodon FOSTER, PAGNAC & HUNT-FOSTER, 2020
Etymology: Greek, megist, "largest," and Greek, odon, "tooth," in reference to the much larger overall size compard with other speices of Amblotherium (A. gracile and A. pusillum), especially as reflected in teeth.

Holotype: SDMS 148545

Locality: Little Houston Quarry (Mammal Pit), V9138, Little Houston Quarry, approximately 20 km west of Sundance in southern Crook County, just north of Little Houston Creek, Black Hills, northeast Wyoming.

Horizon: Member?, Morrison Formation.

Biostratigraphy: Zone?

Age: Age?, Stage?, Malm Epoch, Late Jurassic.

Material:Left dentary preserved in labial viw with p2-p4 and m1-m3 in place.